Physics Bucharest 2017

Clinical lessons - Discussion

 Generally, the benefits of RT greatly outweigh risks for tumor induction! (improvements are needed, increased survival).  Second tumor incidence far from high dose areas is often relatively low (non- IMRT).  Depending on tissue/primary tumor ,… the risk may increase, level off, or decrease at high dose.  If probability of tumor induction levels off, or decreases for higher doses, tumor induction may increase for IMRT and rotational therapy .  High energy photon beams (>10 MV) may result in enhanced tumor induction due to neutron peripheral dose.  Uncertainty in epidemiological data : even studies based on large databases of cancer registries (~100.000 patients) may have conflicting outcome on second cancer incidence. More/better data is needed, e.g. to predict the impact of new techniques such as IMRT or VMAT.

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